1. Field of the Invention
The present invention relates to a power supply circuit, and more particularly to an IC power protection circuit that supplies power to an integrated circuit whose withstand voltage is lower than a supply voltage supplied from the outside.
2. Description of the Related Art
As a power supply circuit for an integrated circuit, JP-A-2005-83221 describes a power supply circuit for a vehicle-mounted electronic control apparatus. The power supply circuit described in JP-A-2005-83221 enables a control power supply for the vehicle-mounted electronic control apparatus while a power switch is off.
Some power supply circuits, including the power supply circuit described in JP-A-2005-83221, receive power supplied from a battery and supply the received power to a CPU (an integrated circuit whose withstand voltage is lower than a supply voltage that is supplied from the outside) via a constant-voltage power supply circuit (regulator).